Guidelines for model calibration and application to flow simulation in the Death Valley regional groundwater system
M. C. Hill, F. A. D’Agnese, C.C. Faunt
2000, Conference Paper, IAHS-AISH Publication
Fourteen guidelines are described which are intended to produce calibrated groundwater models likely to represent the associated real systems more accurately than typically used methods. The 14 guidelines are discussed in the context of the calibration of a regional groundwater flow model of the Death Valley region in the southwestern...
Colorado River sediment transport: 2. Systematic bed‐elevation and grain‐size effects of sand supply limitation
David J. Topping, David M. Rubin, Jonathan M. Nelson, Paul J. Kinzel III, Ingrid C. Corson
2000, Water Resources Research (36) 543-570
The Colorado River in Marble and Grand Canyons displays evidence of annual supply limitation with respect to sand both prior to [Topping et al, this issue] and after the closure of Glen Canyon Dam in 1963. Systematic changes in bed elevation and systematic coupled changes in suspended‐sand concentration and grain...
Predation on Corynorhinus townsendii by Rattus rattus
Gary M. Fellers
2000, Southwestern Naturalist (45) 524-527
Corynorhinus townsendii (Townsend's big- eared bat) is a rare and declining species. Ex- tensive surveys for the coastal subspecies, C. t. townsendii, in California indicate that only 50% of historic maternity colonies are occu- pied currently (Pierson and Rainey, 1996). Three of the largest maternity colonies occur in Marin...
Quantifying precambrian crustal extraction: The root is the answer
D. Abbott, D. Sparks, C. Herzberg, Walter D. Mooney, A. Nikishin, Y.-S. Zhang
2000, Tectonophysics (322) 163-190
We use two different methods to estimate the total amount of continental crust that was extracted by the end of the Archean and the Proterozoic. The first method uses the sum of the seismic thickness of the crust, the eroded thickness of the...
Spatial modeling of the geographic distribution of wildlife populations: A case study in the lower Mississippi River region
W. Ji, C. Jeske
2000, Ecological Modelling (132) 95-104
A geographic information system (GIS)-based spatial modeling approach was developed to study environmental and land use impacts on the geographic distribution of wintering northern pintails (Arias acuta) in the Lower Mississippi River region. Pintails were fitted with backpack radio transmitter packages at Catahoula Lake, LA, in October 1992-1994 and located...
Reservoir characterization of marine and permafrost associated gas hydrate accumulations with downhole well logs
T. S. Collett, Myung W. Lee
2000, Conference Paper, Annals of the New York Academy of Sciences
Gas volumes that may be attributed to a gas hydrate accumulation depend on a number of reservoir parameters, one of which, gas-hydrate saturation, can be assessed with data obtained from downhole well-logging devices. This study demonstrates that electrical resistivity and acoustic transit-time downhole log data can be used to quantify...
A review of the contrasting behavior of two magmatic volatiles: Chlorine and carbon dioxide
J. B. Lowenstern
2000, Conference Paper, Journal of Geochemical Exploration
Chlorine (Cl) and carbon dioxide (CO2) are common magmatic volatiles with contrasting behaviors. CO2 solubility increases with pressure whereas Cl solubility shows relatively little pressure or temperature effect. CO2 speciation changes with silicate melt composition, dissolving as carbonate in basaltic magmas and molecular CO2 in more silicic compositions. In H2O-bearing...
Evaporation from groundwater discharge playas, Estancia Basin, central New Mexico
Kirsten M. Menking, Roger Y. Anderson, Nathaniel A. Brunsell, Bruce D. Allen, Amy L. Ellwein, Thomas A. Loveland, Steven W. Hostetler
2000, Global and Planetary Change (25) 133-147
Bowen ratio meteorological stations have been deployed to measure rates of evaporation from groundwater discharge playas and from an adjacent vegetated bench in the Estancia Basin, in central New Mexico. The playas are remnants of late Pleistocene pluvial Lake Estancia and are discharge areas for groundwater originating as precipitation in...
Voluminous lava-like precursor to a major ash-flow tuff: Low-column pyroclastic eruption of the Pagosa Peak Dacite, San Juan volcanic field, Colorado
Olivier Bachmann, M.A. Dungan, P. W. Lipman
2000, Journal of Volcanology and Geothermal Research (98) 153-171
The Pagosa Peak Dacite is an unusual pyroclastic deposit that immediately predated eruption of the enormous Fish Canyon Tuff (~5000 km3) from the La Garita caldera at 28 Ma. The Pagosa Peak Dacite is thick (to 1 km), voluminous (>200 km3), and has a high aspect ratio (1:50) similar to...
Formation of natural gas hydrates in marine sediments. Gas hydrate growth and stability conditioned by host sediment properties
M. B. Clennell, P. Henry, M. Hovland, J.S. Booth, W.J. Winters, M. Thomas
2000, Conference Paper, Annals of the New York Academy of Sciences
The stability conditions of submarine gas hydrates (methane clathrates) are largely dictated by pressure, temperature, gas composition, and pore water salinity. However, the physical properties and surface chemistry of the host sediments also affect the thermodynamic state, growth kinetics, spatial distributions, and growth forms of clathrates. Our model presumes that...
Natal dispersal in the cooperatively breeding Acorn Woodpecker
Walter D. Koenig, P.N. Hooge, M.T. Stanback, J. Haydock
2000, Condor (102) 492-502
Dispersal data are inevitably biased toward short-distance events, often highly so. We illustrate this problem using our long-term study of Acorn Woodpeckers (Melanerpes formicivorus) in central coastal California. Estimating the proportion of birds disappearing from the study area and correcting for detectability within the maximum observable distance are the first...
Historical eruptions of Merapi Volcano, Central Java, Indonesia, 1768-1998
B. Voight, E.K. Constantine, S. Siswowidjoyo, R. Torley
2000, Journal of Volcanology and Geothermal Research (100) 69-138
Information on Merapi eruptive activity is scattered and much is remotely located. A concise and well-documented summary of this activity has been long needed to assist researchers and hazard-mitigation efforts, and the aim of this paper is to synthesize information from the mid-1700s to the present. A descriptive chronology is...
Root growth and function of three Mojave Desert grasses in response to elevated atmospheric CO2 concentration
C.K. Yoder, P. Vivin, L.A. DeFalco, J.R. Seemann, R.S. Nowak
2000, New Phytologist (145) 245-256
Root growth and physiological responses to elevated CO2 were investigated for three important Mojave Desert grasses: the C3 perennial Achnatherum hymenoides, the C4 perennial Pleuraphis rigida and the C3 annual Bromus madritensis ssp. rubens. Seeds of each species were grown at ambient (360 μl l−1) or elevated (1000 μl l−1)...
A preliminary report on the 1999 Chi-Chi (Taiwan) earthquake
T. C. Shin, K.W. Kuo, W.H.K. Lee, T.L. Teng, Y.B. Tsai
2000, Seismological Research Letters (71) 24-30
No abstract available....
Reactive transport of metal contaminants in alluvium: Model comparison and column simulation
J. G. Brown, R.L. Bassett, P. D. Glynn
2000, Applied Geochemistry (15) 35-49
A comparative assessment of two reactive-transport models, PHREEQC and HYDROGEOCHEM (HGC), was done to determine the suitability of each for simulating the movement of acidic contamination in alluvium. For simulations that accounted for aqueous complexation, precipitation and dissolution, the breakthrough and rinseout curves generated by each model were similar. The...
Isotope hydrology dynamics of riverine wetlands in the Kankakee Watershed, Indiana
W.C. Sidle, L. Arihood, R. Bayless
2000, Journal of the American Water Resources Association (36) 771-790
Wetland restoration activities may disturb shallow ground-water flow dynamics. There may be unintentional sources of water flowing into a constructed wetland that could compromise the long-term viability of a wetland function. Measurement of naturally-occurring isotopes in the hydrosphere can provide an indication of provenance, flow paths or components, and residence...
Age-specific breeding in Emperor Geese
Joel A. Schmutz
2000, The Wilson Bulletin (112) 261-263
I studied the frequency with which Emperor Geese (Chen canagica) of known age were observed breeding on the Yukon-Kuskokwim Delta, Alaska. No one- or two-year old geese were observed on nests. Three-year old geese bred at a lower rate than four-year old geese. These data suggest that patterns...
Factors associated with plant species richness in a coastal tall-grass prairie
James B. Grace, Larry K. Allain, Charles Allen
2000, Journal of Vegetation Science (11) 443-452
In this study we examine the factors associated with variations in species richness within a remnant tall-grass prairie in order to gain insight into the relative importance of controlling variables. The study area was a small, isolated prairie surrounded by wetlands and located within the coastal prairie region, which occurs...
A genetic evaluation of morphology used to identify harvested Canada geese
John M. Pearce, Barbara J. Pierson, Sandra L. Talbot, Dirk V. Derksen, Donald K. Kraege, Kim T. Scribner
2000, Journal of Wildlife Management (64) 863-875
Using maximum likelihood estimators (in genetic stock identification), we used genetic markers to evaluate the utility of 2 morphological measures (culmen length and plumage color) to correctly identify groups of hunter-harvested dusky (Branta canadensis occidentalis) and dusky-like Canada geese on the wintering grounds within the Pacific Flyway. Significant levels of...
Field evaluation of lead effects on Canada geese and mallards in the Coeur d'Alene River Basin, Idaho
Charles J. Henny, L. J. Blus, D. J. Hoffman, L. Sileo, Daniel J. Audet, Mark R. Snyder
2000, Archives of Environmental Contamination and Toxicology (39) 97-112
Hatch year (HY) mallards (Anas platyrhynchos) in the Coeur d'Alene (CDA) River Basin had higher concentrations of lead in their blood than HY Western Canada geese (Branta canadensis moffitti) (geometric means 0.98 versus 0.28 μg/g, wet weight). The pattern for adults of both species was similar,...
Sources and yields of dissolved carbon in northern Wisconsin stream catchments with differing amounts of Peatland
John F. Elder, Nancy B. Rybicki, Virginia Carter, Victoria Weintraub
2000, Wetlands (20) 113-125
In five tributary streams (four inflowing and one outflowing) of 1600-ha Trout Lake in northern Wisconsin, USA, we examined factors that can affect the magnitude of stream flow and transport of dissolved organic and inorganic carbon (DOC and DIC) through the streams to the lake. One catchment, the Allequash Creek...
Stress history and geotechnical properties of sediment from the Cape Fear Diapir, Blake Ridge Diapir, and Blake Ridge
W.J. Winters
2000, Conference Paper, Proceedings of the Ocean Drilling Program: Scientific Results
Geotechnical properties of sediment from Ocean Drilling Program Leg 164 are presented as: (1) normalized shipboard strength ratios from the Cape Fear Diapir, the Blake Ridge Diapir, and the Blake Ridge; and (2) Atterberg limit, vane shear strength, pocket-penetrometer strength, and constant-rate-of-strain consolidation results from Hole 995A, located on the...
Response of hatchling and yearling turtles to thermal gradients: Comparison of Chelydra serpentina and Trachemys scripta
R. Bruce Bury, A.B. Nebeker, M. J. Adams
2000, Journal of Thermal Biology (25) 221-225
In laboratory tests, young Chelydra serpentina and Trachemys scripta altered their distribution in the presence of a temperature gradient. Selection of temperatures in the gradient for hatchlings and yearlings showed that body temperatures (Tbs) of C. serpentina were lower than T. scripta, but the difference was insignificant. Relatively low Tbs...
Gravitational stability of three-dimensional stratovolcano edifices
M.E. Reid, S.B. Christian, D.L. Brien
2000, Journal of Geophysical Research B: Solid Earth (105) 6043-6056
Catastrophic flank collapses have occurred at many stratovolcanoes worldwide. We present a three-dimensional (3-D) slope stability analysis for assessing and quantifying both the locations of minimum edifice stability and the expected volumes of potential failure. Our approach can search the materials underlying a topographic surface, represented as a digital elevation...
Sr and Nd isotopic compositions, age and petrogenesis of A-type granitoids of the Vernon Supersuite, New Jersey Highlands, USA
R.A. Volkert, M.D. Feigenson, L.C. Patino, J.S. Delaney, Avery A. Drake Jr.
2000, LITHOS (50) 325-347
Voluminous late Mesoproterozoic monzonite through granite of the Vernon Supersuite underlies an area of approximately 1300 km2 in the Highlands of northern New Jersey. The Vernon Supersuite consists of hastingsite ?? biotite-bearing granitoids of the Byram Intrusive Suite (BIS) and hedenbergite-bearing granitoids of the Lake Hopatcong Intrusive Suite (LHIS). These...
